Conventional ultrasound systems generally include an ultrasound probe formed from a plurality of transducers which define an aperture of the ultrasound probe. The transducers can be arranged spatially and can be divided into a plurality of sub-apertures or sub-arrays. Sub-aperture processors (SAPs) may perform beamforming operations for the elements within the sub-aperture, on both transmit and/or receive operations. A typical ultrasound system generally further includes a receive and/or transmit beamformer that is external to the probe and that is connected to the transducer elements by electrical cables.
The beamformer generally focuses and steers ultrasound energy transmitted and received by the probe to acquire acoustic reverberation data as one step in generating images of anatomic content on a display. In particular, the transmit beamformer generates pulse or continuous signals and the plurality of transducers convert electrical signals to pressure waves and vice versa. The pressure waves generally propagate through tissue and part of the ultrasound energy is reflected back to the transducers. The receive beamformer processes the received ultrasound echoes and focuses the energy. The ultrasound signals are then processed and converted into an audio output and/or a visual display at a graphical user interface (GUI).
As described above, each ultrasound waveform is output by the probe via a respective channel. In conventional (non-3D) ultrasound systems, each transducer element is normally associated with a distinct cable or wire connecting the probe to the beamformer to facilitate processing of the respective ultrasound signal, e.g., geometrical calculations are required for each transducer element for steering. For 3D ultrasound systems with thousands of individual elements, a distinct cable is not feasible. To deal with the thousands of elements, transmission is handled by distribution of a set of transmit signals from the system or with transmitters in the probe. Receiving is handled with a combination of beamforming in the probe and/or system. The probe beamforming can be analog and/or digital. A digital solution requires an analog-to-digital (ADC) converter in the probe. Since each channel can have an ADC, some implementations can require thousands of ADCs. As a result, the implementation of a beamformer in the probe may require one or a plurality of application specific integrated circuits (ASIC) and a technical solution that makes it possible to fit the circuitry needed within the required restrictions on silicon area, power, setup data, calculation time, and the like.
Thus, a need exists for ultrasound probes with means for reducing the complexity for implementing a dynamic beamformer. These and other needs are addressed by the ultrasound probes and associated systems and methods of the present disclosure.